Surely the problem is that email is a relatively blunt tool to track bugs and fixes?
Something web-based that lets you track the bug over time, relate it to duplicates, attach
patches, make comments, etc, would seem a better idea - by having subsystem tags such as SCSI
you could also enable smaller groups of developers to focus on their area. Also, maybe the
kernel needs bug triage people who simply prioritise and tag bugs so they find their way to
the right developer community.